Question Using a custom pass to render layer(s) at a different FoV

I have an URP project and am testing bringing it into HDRP. My URP project made heavy use of camera stacking, which seems to still be prohibitively expensive to use in HDRP. Most of the things I was using camera stacking for can be adapted to the custom pass model easily enough, but I'm hung up on one.

In URP, much of my 'UI' was meshes captured by an orthographic overlay camera. I'm having trouble finding the 'intended' way to replicate this effect in HDRP, if there is one. The problem sort of superficially resembles the 'FPS hands' one, but that seems to be in a strange state too, since whatever FoV slider used to exist on the HDRP Lit shader has been deprecated—and I don't really want this stuff handled by a shader property anyway, since I'm using TMPro meshes, worldspace canvas elements, etc., on this UI layer.

Using a custom pass seems like the nearest thing, and one throwaway line from the HDRP docs maybe confirms this:

But I can't find anything else about what this is referring to or how I might get started on this.

Am I on the right track? Does anyone have any advice on how I might go about doing this?

Thanks!